Stocks don't take personality tests. They don't have MySpace pages to gauge their friendly attraction. They don't keep slam books. They don't split "Best Friends" lockets in half.

If someone were to ask you about the stocks that we love the most in the U.S., how would you answer that? Trading volume? Number of shareholders of record? Lowest short interest ratio?

They are all flawed metrics in this regard. They fancy bulk over emotion. They side with temporary speculation over permanent passion.

I have a better measuring stick. When I want to weigh our collective amorous weight in specific equities, I like to go to the list of the most popular orders at The site specializes in selling single-share stock certificates as gifts. When you're willing to pay the transfer fee for a single stock, and sometimes even frame it with a personalized plaque, well, that's love, my friend.

How do I love thee? Let me count the odd-lot ways
When my oldest son was born, we decided to decorate his playroom with a circus theme. No clowns -- they're just creepy. We just wanted to duplicate the jovial nature of a day at the carnival. As a stock lover, my contribution to the decor was a single share of Circus Circus stock. It proved to be a nice conversation piece. And, yes, it appreciated nearly threefold on the way to its eventual buyout.

That's why I can certainly vouch for the notion that a single-share investor's commitment is just as strong -- if not more so -- than the investor laying it on the line in larger sums on the same company.

Let's take a look at the five most popular stocks, according to OneShare:

1. Pixar (NASDAQ:PIXR) - The world's leader in computer animation is a natural at the top. Pixar is batting 1,000 when it comes to producing family-friendly blockbusters. That's the kind of average that other studios -- in live action and theatrical animation -- just can't match. To be fair, Pixar is being promoted by OneShare as a valuable keepsake. Once the company's likely merger is completed over the summer, they just won't be printing shares of Pixar anymore.

2. Disney (NYSE:DIS) - Who is Pixar merging with again? That's right, Disney. The Mickey Mouse company is an odd-lot favorite. It's usually the top draw at OneShare, with uncles, aunts, and grandparents gifting their newborn relatives with a little fiscal pixie dust. Disney's theme parks and media networks have been running superbly lately. Swallowing Pixar will help it regain its once-astronomical lead in animation.

3. Harley-Davidson (NYSE:HDI) - Yes, folks can get pretty passionate about their Harleys. The company has been motoring for more than 100 years. It has also posted record earnings for 20 consecutive years. Longtime owners of the company are in hog heaven. The shares have averaged 27% in annualized returns since 1990. As far as investment vehicles go, this has been one snazzy ride.

4. Ford (NYSE:F) - Like a rock? Is it the Bob Seger marketing slogan for rival Chevrolet or a description of how Ford shares have been falling lately? Either way, Ford owners are apparently passionate enough about Ford to make it a popular gift item. OneShare offers GM and Chrysler parent DaimlerChrysler as well, but they're not even close to Ford in order popularity. That's why, as bad as Ford's problems appear to me -- and trust me, they're pretty bad -- I get the feeling that the brand is strong enough to weather the cyclical storm.

5. DreamWorks Animation (NYSE:DWA) - Pixar? Disney? With DreamWorks Animation, we now have the three leading studios in the field of theatrical animation in the top five list. To DreamWorks' credit, it really has come a long way since the so-so likes of Antz and The Road to El Dorado. Shrek was ogre enough to topple Pixar's Monsters, Inc. as the top animated draw in 2001. Recent releases like Madagascar and Shark Tale have cemented the company's reputation as a powerhouse brand.

All you need is love
There's plenty of love in those five American institutions. I'll admit that some of the findings surprised me. I figured that Apple Computer (NASDAQ:AAPL) would have been a shoo-in, though it only clocks in at the ninth slot on the list at the moment. Other companies with fanatical fans, like Sirius Satellite Radio (NASDAQ:SIRI), are actively offered by OneShare, but they didn't even make the cut.

You know what didn't surprise me? Two of the five stocks on the list -- Pixar and DreamWorks Animation -- have been recommended to Motley Fool Stock Advisor newsletter service subscribers.

David and Tom Gardner have been presenting their best stock ideas side by side for years now, and it's only natural that the two stock-picking masters should happen to single out the companies that we collectively wind up loving -- or owning.

The premium research service's aim is pretty simple: To build lasting wealth for you and your family by helping you find deeply undervalued stocks.

David and Tom aren't just coming back with low-P/E stocks on a trailing basis. That would be a silly scale to quantify "deeply undervalued stocks." Instead, they pick companies poised for greatness; in retrospect, they'll look like huge bargains at the time of their initial recommendation.

Does that sound like a winning strategy? You bet. The average Stock Advisor pick has appreciated by 61.8%, several times better than the 21.1% average return generated by the market in that time. If you want to associate yourself with that kind of quest for superior investing ideas, you may want to consider subscribing for a year or two. If you're still not sure, why don't you give it a shot for the next four weeks -- at no cost -- with a free trial subscription.

It's what falling in love with stocks -- and investing -- is all about.

Longtime Fool contributor Rick Munarriz can be a lovebird when it comes to certain stocks. He happens to own shares of Pixar and Disney. T he Fool has a disclosure policy. Rick is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early.